Pancreas, Insulin, Glucagon, Somatostatin, Diabetes Mellitus, Adrenal Gland, Glucocorticoids, Mineralocorticoids, Posterior Pituitary Hormones, Local Hormones

1. PANCREAS
By
Dr. Faraza Javaid

2. PANCREATIC ISLETS
The endocrine pancreas consists of
cluster of cells, known as islets (islets
of Langerhans), scattered throughout
the gland.
Pancreatic hormones are secreted
directly into the blood stream and
circulate throughout the body.

3. CELLS TYPES
There are 3 main types of cells in islets:
Alpha cells – secrete Glucagon
Beta cells – secrete insulin
Delta cells – secrete somatostatin (IH)

4. INSULIN
Insulin main function is to lower raised blood
nutrients levels, not only glucose but also
amino acids and fatty acids.
Major actions are:
 Acting on cell membrane and stimulating
uptake of glucose by muscle and
connective tissues
 Increase conversion of glucose to glycogen
 Synthesize protein
 Promote fatty acid synthesis and fat
storage in adipose tissue
 Decrease glycogen breakdown into glucose

5. GLUCAGON
Glucagon increases blood glucose levels by
stimulating:
Conversion of glycogen to glucose

6. SOMATOSTATIN
This hormone is produced by hypothalamus
and islets cells,
inhibits the secretion of insulin and
glucagon
in addition to inhibiting the secretion of GH
from anterior pituitary.

8. DIABETES MELLITUS
The most common endocrine
disorder.
 Primary DM (TYPE 1 and TYPE 2)
 Secondary DM
 Gestational DM

13. ADRENAL GLAND

14. Adrenal Gland
 Adrenal glands are called the
‘life-saving glands’ or
‘essential endocrine glands’.
 It is because the absence of
adrenocortical hormones
causes death within 3 to 15
days and absence of
adrenomedullary hormones,
drastically decreases the
resistance to mental and
physical stress.

15. PARTS OF ADRENAL GLAND
Adrenal gland is made of two distinct
parts:
1. Adrenal cortex: Outer portion,
constituting 80% of the gland
2. Adrenal medulla: Central portion,
constituting 20% of the gland.

16. ADRENAL CORTEX
Adrenal cortex produces three groups of
steroids hormones from cholesterol.
They are collectively called
adrenocorticoids.
 Glucocorticoids
 Mineralocorticoids
 Androgen

17. GLUCOCORTICOIDS
Cortisol or
(Hydrocortisone) is
the main
glucocorticoid but
small amount of
corticosterone and
cortisone are also
produced.
STERIOD HORMONES

18. Effects of Glucocorticoids
 Hyperglycemia
 Lipolysis
 Stimulate protein breakdown
 Promote sodium and water retention

19. MINERALOCORTICOID
Aldosterone is the main mineralo-
corticoid

21. ADRENAL MEDULLA
The medulla is completely surrounded
by the adrenal cortex. When stimulated
by extensive sympathetic nerve supply,
the gland releases:
 Adrenaline/ Epinephrine
 Nor-adrenaline/ Nor-epinephrine

23. Fight or Flight Response
 Increase heart rate
 Increase blood pressure
 Vasoconstriction
 Increase metabolism
 Dilate pupil/ Mydriasis

25. Other Hormones of Ant. Pituitary
1. Follicle-stimulating Hormone (FSH)
In males, FSH acts along with testosterone and
accelerates the process of spermiogenesis. In
females, FSH promotes the aromatase activity in
granulosa cells, resulting in conversion of
androgens into estrogen.
2. Luteinizing Hormone (LH)
In males, This hormone is essential for the
secretion of testosterone. In females, Induces
synthesis of androgens from the cells of growing
follicle and is responsible for ovulation
3. Prolactin
Prolactin is necessary for the preparation of
mammary glands for the production and secretion
of milk.

26. POSTERIOR PITUITARY
 Posterior pituitary is made up of neural type
of cells called pituicytes and unmyelinated
nerve fibers.
 Actually, the posterior pituitary does not
secrete any hormone. ADH and oxytocin are
synthesized in the hypothalamus.
 In the posterior pituitary, these hormones
are stored at the nerve endings. Whenever,
the impulses from hypothalamus reach the
posterior pituitary, these hormones are
released from the nerve endings into the
circulation. Hence, these two hormones are
called neurohormones.

27. OXYTOCIN
Oxytocin stimulates two target tissues
during and after childbirth.
 Uterine smooth muscle
 Muscle cells of lactating breast

29. AntidiUretic Hormone/ Vasopressin

30. DISORDERS OF ANT.
PITUITARY GLAND

31. DISORDERS OF ANT. PITUITARY
Gigantism and Acromegaly
 Excessive bone growth
 Enlargement of organs
 Formation of excess tissues
 Enlargement of heart and BP
 Increased metabolism
Dwarfism
This is caused by severe deficiency of
growth hormone

32. CUSHING SYNDROME
 It is also a rare disease characterized by
obesity.
 Cushing disease develops by adenoma of
Adrenal gland. It increases the secretion of
adrenocorticotropic hormone, which in turn
stimulates the adrenal cortex to release
cortisol.
 Cushing disease also develops by hyperplasia
or tumor of adrenal cortex.

34. SIMMOND’S DISEASE
 Simmond disease is a rare pituitary
disease.
 It occurs mostly in hypopituitarism,
i.e. hyposecretion of all the anterior
pituitary hormones due to the atrophy
or degeneration of anterior pituitary

35. DISORDER OF POST. PITUITARY

36. PHEOCHROMOCYTOMA

37. Endocrine Functions of Other Organs

38. LOCAL HORMONES
Classification of Local Hormones
Local hormones are classified into two types:
I. Hormones synthesized in tissues
II. Hormones synthesized in blood.
LOCAL HORMONES SYNTHESIZED IN TISSUES
Local hormones synthesized in the tissues are:
1. Prostaglandins and related substances
2. Other local hormones synthesized in tissues.
(Acetylcholine, Serotonin, Histamine, Substance P,
Heparin, Leptin, Gastrointestinal hormones).
LOCAL HORMONES SYNTHESIZED IN BLOOD
1. Kinins

40. ACETYL CHOLINE
Acetylcholine is the cholinergic
neurotransmitter. It is the transmitter
substance at neuromuscular junction. It is also
secreted by other nerve endings and other
cells and control parasympathetic system
(Rest and Digest).
Acetylcholine:
i. Produces excitatory function of synapse by
opening the sodium channels
ii. Activates smooth muscles in GI tract,
urinary tract and skeletal muscles
iii. Inhibits cardiac function
iv. Causes vasodilatation.

41. SEROTONIN
Serotonin is otherwise known as 5-
hydroxytryptamine (5-HT).
HAAPY HORMONE
Serotonin:
i. Inhibits impulses of pain sensation in
posterior gray horn of spinal cord
ii. Causes mood elevation and induces
sleep
iii. Causes vasoconstriction.

42. Histamine
i. It is an excitatory neurotransmitter
substance
ii. Histamine released from tissues causes
vasodilatation and enhances the capillary
permeability for fluid and plasma proteins from
blood into the affected tissues. So, the
accumulation of fluid with proteins develops
local edema
iii. In GI tract, histamine increases the motility.

43. KININS
Kinins are biologically active protein hormones
which are circulating in blood.
Kinins:
 Dilates the blood vessels and decreases the
blood pressure. It is considered as a potent
vasodilator
 Increases the blood flow throughout the body
by its vasodilator action
 Increases permeability of capillaries during
inflammatory conditions, resulting in edema
in the affected area
 Stimulates pain receptors

44. Thank You